The desire to reduce automotive fuel consumption and emissions has been well documented. Electrified vehicles are being developed that reduce or completely eliminate reliance on internal combustion engines. In general, electrified vehicles differ from conventional motor vehicles because they can be selectively driven by one or more battery powered electric machines. Conventional motor vehicles, by contrast, rely exclusively on the internal combustion engine to propel the vehicle.
Electrified vehicles may include a high voltage traction battery pack for powering various high voltage loads of the vehicle and an auxiliary battery for powering various low voltage loads of the vehicle. The high voltage battery pack and the low voltage auxiliary battery of some electrified vehicles, such as battery electric vehicles (BEV) and plug-in hybrid electric vehicles (PHEV), are typically charged using energy from a utility grid or other off-board power source. During some auxiliary battery charging conditions, the power drawn by a power converter may be greater than the power that can be provided by the charging system, thereby potentially discharging the high voltage battery pack in order to support the low voltage charging.